How do you know a journal is legitimate?

As a researcher or scholar, you may receive solicitations to submit articles for publication from unfamiliar publishers via email. Some of these offers are legitimate, but others turn out to be scams. There are a few basic steps you can take to evaluate these journals.

The tried and true method for checking out a journal is to visit its website, research associated scholars and the publisher online, and above all talk to colleagues. But you can also look for the following information:

Basic indicators of legitimacy

All scholarly journals

Does the website list any fees which authors may be charged for publishing their article (yes, subscription journals can charge fees too)?

Open Access scholarly journals

Is the journal listed in the Directory of Open Access Journals (DOAJ)?
The DOAJ vets Open Access journals before including them in the database, and it is currently making its process even more vigorous.

Is the publisher a member of the Open Access Scholarly Publishers Association (OASPA)?
Many of the largest open access publishers are members of the OASPA, though there are legitimate open access publishers that do not belong.

While this list isn't exhaustive, the more ties to well-known organizations and the more a journal follows best practices, the more likely it is to be a legitimate operation.